1. Field of the Invention
The invention relates to DC voltage conversion, in particularly to switching regulators with slope compensation and slope compensation method thereof.
2. Description of the Related Art
Battery life is a major consideration for portable electronic systems. This is particularly true for consumer electronics, such as cellular phones, digital cameras, portable computers and other handheld equipment. Designers of these products are faced with a continual need to reduce package size (and battery size) while increasing battery life to match or exceed competitive products.
To maximize battery life, it is necessary to optimize the performance of a wide range of different electronic components. Among the most important of these components are voltage regulators. In portable electronic systems, these devices perform a range of power handling tasks including increasing, decreasing and inverting voltage.
FIG. 1 shows a voltage-mode control switching regulator that converts high DC voltage to lower. The advantages of voltage-mode control are ease of analysis and a large ramp wave providing good noise immunity. However, in terms of transient-response, because any change in line or load must first be detected by the feedback resistor divider and then responded to via error amplifier and PWM generator, response speed is reduced. Further, because the output L-C network provides a complex-pole pair and the loop gain varies with the input voltage, loop compensation design is much more complicated.